It's been a busy winter, and I've put more miles on my car over the past few months than I did all last year, I suspect, as I've been working in the office of one of my clients rather than from home, as usual.

One of the downsides of so much driving is, of course, the risk of getting stuck in traffic. And when a copy editor gets stuck in traffic, she sometimes starts copy-editing the bumper stickers and other signage on the vehicles around her.

I spent a few minutes the other day behind a panel truck that proclaimed that the fleet it was part of produced "50 percent fewer emissions." One may ask, fewer than what? I can appreciate the effort behind "fewer" emissions rather than "less" emissions – remember the flap over the "10 items or less" lines at the supermarket? But still, someone seemed unclear on the distinction between "mass nouns" and "count nouns."

Item is a count noun: one item, many items, more or fewer items. Money, on the other hand, is a mass noun, or "uncountable," as some authorities refer to it, such as the Macmillan dictionary. It sounds silly to say you can't "count" your money, but what's meant is that the word doesn't form a plural by adding "s." One speaks of having much money or more money, but not, ordinarily, of "many moneys."

The case of emissions is a little different. I need to get my car tested for "emissions" this month. And there will be more than one kind of gas the tester is concerned about. But the concern will be about how much of each kind of gas my little chariot produces, not how many emissions.

Something else I notice on the vehicles of my fellow travelers on the road is – gasp! – misuse of postal abbreviations for states. Journalism fights what's looking ever more like a rear-guard action in favor of "traditional" abbreviations for states: e.g., "Ashland, Mass.," rather than "Ashland, MA." Our rule is that "MA" and its brethren are proper only in close proximity to a ZIP Code – in a full postal address, rather than a passing reference. But usage is changing, and I'm resigning myself to seeing things like "Flanagan Brothers Plumbing, Ashland, MA." (My apologies in advance to the Flanagan Brothers, who are not, as far as I know, in Ashland, with trucks in need of a copy editor.)

Where I draw the line, in peripatetic mode, though, is at "Ashland, Ma.," especially when it appears in that old-fashioned turn-of-the-last-century script – perhaps meant to suggest circus wagons. That style of lettering predates ZIP Codes by well over half a century.

Speaking of peripatetic: It's rooted in a Greek word meaning " 'given to walking about,' especially while teaching." So it appears I'm stretching it a bit to apply it to driving around. The word has a strong connection with Aristotle. The Online Etymology Dictionary notes, "Aristotle's custom was to teach while strolling through the Lyceum in Athens."

Maybe there's a connection with driving. The upside of all my time on the road is that it does give me time to think. New insights flash into thought to suggest ways to solve problems I didn't realize I was still pondering. And so it was the other day. I had an answer to my "emissions" problem: Maybe the truck I saw should have said simply, "Our vehicles emit 50 percent less greenhouse gas."